For problem #4 the answer is 100°. The triangle are congruent meaning the angles that are given both of the triangle have to have the same angles.
The triangle sum theorem is all triangles have a 180° . All the 3 angles = 180.
They gave you two angles of the triangle. So add the two angles and find the difference of 180.
50+30=80
180-80=100°
#5 set those 2 angles equal. Because the A corresponds to Q. Solve for X and plug in your x value
